Update OTS to revision 99a3b7f

third_party/ots/src/layout.cc

Index: third_party/ots/src/layout.cc
diff --git a/third_party/ots/src/layout.cc b/third_party/ots/src/layout.cc
index 7f467221a89b3ea569039820b6491a0813af0a18..e4f8070f32870931730f63bdb1403321a29c6165 100644
--- a/third_party/ots/src/layout.cc
+++ b/third_party/ots/src/layout.cc
@@ -195,16 +195,21 @@ bool ParseLookupTable(ots::Font *font, const uint8_t *data,
   // Check lookup flags.
   if ((lookup_flag & kGdefRequiredFlags) &&
       (!font->gdef || !font->gdef->has_glyph_class_def)) {
-    return OTS_FAILURE_MSG("Bad lookup flags %d", lookup_flag);
+    return OTS_FAILURE_MSG("Lookup flags require GDEF table, "
+                           "but none was found: %d", lookup_flag);
   }
   if ((lookup_flag & kMarkAttachmentTypeMask) &&
       (!font->gdef || !font->gdef->has_mark_attachment_class_def)) {
-    return OTS_FAILURE_MSG("lookup flag asks for mark attachment that is bad %d", lookup_flag);
+    return OTS_FAILURE_MSG("Lookup flags ask for mark attachment, "
+                           "but there is no GDEF table or it has no "
+                           "mark attachment classes: %d", lookup_flag);
   }
   bool use_mark_filtering_set = false;
   if (lookup_flag & kUseMarkFilteringSetBit) {
     if (!font->gdef || !font->gdef->has_mark_glyph_sets_def) {
-      return OTS_FAILURE_MSG("lookup flag asks for mark filtering that is bad %d", lookup_flag);
+      return OTS_FAILURE_MSG("Lookup flags ask for mark filtering, "
+                             "but there is no GDEF table or it has no "
+                             "mark filtering sets: %d", lookup_flag);
     }
     use_mark_filtering_set = true;
   }